Metamath Proof Explorer


Theorem 2p1e3

Description: 2 + 1 = 3. (Contributed by Mario Carneiro, 18-Apr-2015)

Ref Expression
Assertion 2p1e3 2+1=3

Proof

Step Hyp Ref Expression
1 df-3 3=2+1
2 1 eqcomi 2+1=3